Question

find the value of x...
in the given figure..

Answer 1

In figure (i) let angleOBC = m and angleOCB= n
in ABC
70 + 2m + 2n = 180
2m +2n=110
m + n = 55

and in OBC
x + m + n = 180
x= 180 - 55 = 125...



in figure ii
let angleCBO= m and angleOCB= n

in ABC
60 + ( 180 - 2m) + (180 - 2n)= 180
solve it and u get

240 = 2m + 2n
m + n = 120

in BCO
x + m + n = 180
x =180-120
x = 60